This is the cheapest price I have seen the Temple of Ultimate Weapon for. The next best price I have seen for the Ninjagoset is at Tesco/Very who are selling it for £63.70 (but without the Lego DC set which Amazon is including for free).

Amazon are also offering a free £5 if you top up £50.00 deal which means you can get both sets for £54.99. If you top up your Amazon account immediately before purchase